Threats / Apple / CVE-2023-42916
CVE-2023-42916
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-08-04
Apple Multiple Products vulnerability
Out-of-bounds read in WebKit affects Apple iOS, iPadOS, macOS, and Safari. Processing malicious web content may disclose sensitive information. Vulnerability is actively exploited in the wild.
Verdict
Today item — known-exploited.
An out-of-bounds read in WebKit's HTML parsing allows attackers to extract sensitive data by crafting malicious web content. The vulnerability affects multiple Apple platforms and third-party products using WebKit. Active exploitation has been confirmed.
CISA KEV Yes · 2023-12-044EPSS 0.17823 (verify live)5CVSS 6.5 (CISA)3CISA SSVC Exploitation: active · Automatable: no · Impact: partial3
01
Is it exploitable?
— the evidence, ranked above the scoreReported exploitation
6 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-12-04).
Probability (EPSS)
EPSS 0.17823 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N) · Affected: Apple, Multiple Products. Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
Weakness (CWE)
Mapped to CWE-125 Out-of-bounds Read — weakness family: Memory safety.CWE assignment from the public NVD record (may be stale); the weakness class drives how the flaw is exploited.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · Technical Impact: partialCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog 4 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
Craft malicious HTML or web content designed to trigger out-of-bounds memory access in WebKit parser
Business
User devices running affected Apple platforms or WebKit-dependent applications become vectors for information disclosure
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
Deliver malicious content via web browsing, email links, or embedded content to trigger the parsing vulnerability
Business
Sensitive data resident in adjacent memory regions is read and exfiltrated, compromising user privacy and confidentiality
3
Lateral reach — past segmentation narrative 3
Attacker
Repeat exploitation across multiple users and devices to harvest disclosed information at scale
Business
Widespread data exposure undermines trust in affected platforms and creates liability for organizations relying on WebKit
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05